Doubts on progress and technology

Fighting marine debris: the dustcarts of the sea

Considering that the oceans hold more garbagethan fish by now, this
might be the right time to retrain our fishermen and let them hunt for
litter. Several
companies offer equipment to fish garbage out of rivers, lakes and
harbours. They say they could build larger dustcarts for seas and
oceans, too. Send the bill to the disposables industry -
and let the cleanup begin.

The British company Water Witch offers two boats that are especially designed to clean up marine debris. The Buddy Catamaran
(above and below) is a litter retrieval and waterway maintenance boat
for marinas, harbours and inland waterways.

Built from aluminium and
designed for ease of operation and low cost of
ownership, this road-transportable vessel features a removable basket,
which can
be lifted and tipped directly into a skip or shore side receptacle for
disposal. The boat can filter a water surface of 92 x 92 metres per
hour. The filter system can be adjusted to collect different sizes of
flotsam.

The Water Witch workboat (below) could be compared to a floating bulldozer and features a powerful front end loader which can
lift up to 1000 kg and reach to 3.65m below the waterline. About 100 of them are in use worldwide. A
quick-release system ensures a range of loader attachments can be
easily fitted in seconds. Attachments available include dredge buckets,
log grapples, weed cutters/rippers, access platforms, cranes and more.

Modular skip barges
allow recovered debris and
waste to be stored and transported using transfer skips employed by
waste removal contractors worldwide. Each barge features quick-connect
couplings to allow additional units to be connected to suit capacity
requirements.

Jackie Caddick, director of Water Witch, recently said in an interview
that they could easily build much larger versions of their dustcarts if
the money is available (source, in Dutch). Much larger garbage barges already exist (more here) :

The BBC points to 2 large skimmer boats (Thames Clearwater I & II, below) in the river Thames, custom built by Damen Shipyards in the Netherlands and launched
in September 2007.
The catamarans (24 metres long and 8.20 metres wide)
are outfitted with the screening technology currently employed in
land-based facilities.

The screens, located near midships, are
designed to pick up small debris which is then deposited into storage
containers located on deck. Larger debris is captured at the bow in
coarse mesh buckets, which also allows the smaller items to pass
through and move towards the finer debris screens that are found
midships.

Spanish company Marnett offers totally different floating dustcarts, like the one below :

In the US, skimmer boats have been in use since the early 1980s. United Marine International manufactures the TrashCat, which comes in 3 sizes (pictures below). About 100 of them are in use worldwide. They are
capable of collecting up to 1200 cubic feet (34 cubic meters) of
floating debris per load. US company Alpha Boats sells similar machines.

Maybe we don't even need new boats. Fishing boats are very good at (unintentionally) catching marine debris. Fishing for litter is a North Sea project that encourages fishermen to collect garbage
they find in their fishing nets. The cooperation of the vessels and
their crew is without financial compensation, but recently a Belgian
minister decided to pay fishermen 10 euro per garbage bag they bring on
shore.

The Chinese Wheelbarrow

How to downsize a transport network: the Chinese wheelbarrowFor being such a seemingly ordinary vehicle, the wheelbarrow has a surprisingly exciting history. This is especially true in the East, where it became a universal means of transportation for both passengers and goods, even over long distances.

Human Powered Cranes

Wood Gas Vehicles

Firewood in the Fuel Tank: Wood Gas VehiclesWood gas cars are a not-so-elegant but surprisingly efficient and ecological alternative to their petrol (gasoline) cousins, whilst their range is comparable to that of electric cars.

Open Modular Hardware

How to make everything ourselves: open modular hardwareConsumer products based on an open modular system can foster rapid innovation, without the drawback of wasting energy and materials. The parts of an obsolete generation of products can be used to design the next generation, or something completely different.

Power from the Tap

Power from the Tap: Water MotorsJust before the arrival of electricity at the end of the 19th century, miniature water turbines were connected to the tap and could power any machine that is now driven by electricity.